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1.
Article in English | MEDLINE | ID: mdl-38807745

ABSTRACT

The European Society of Cardiology guidelines for the management of adult congenital heart disease patients recommend screening for arrhythmias and bradycardias in symptomatic patients, often being done by means of an ambulatory 24-48-hour Holter or implantable loop recorder (ILR). However, nowadays non-invasive instruments, such as patches, smartwatches and smartphones based on single-lead ECGs that perform extended monitoring, are also available. The aim of this narrative review was to assess whether these instruments, when they detect arrhythmias and bradycardias in patients with adult congenital heart disease, will lead to meaningful changes in clinical care. Clinically meaningful changes include adjustment of medication, cardioversion, electrophysiology study, ablation or implantation of a cardiovascular implantable electronic device. The following monitoring instruments are discussed: cumulative Holter, 2-week continuous monitor, smartwatchand smartphone-based single-lead ECG, and ILR. The diagnostic yield of extended rhythm monitoring is high, and varies between 18% (smartphone-based single-lead ECG) and 41% with ILR. In conclusion, contemporary arrhythmia screening includes various new non-invasive technologies that are promising new tools as an alternative to Holter monitoring or ILR. However, the optimal mode of detection is still unclear due to the lack of head-to-head comparisons.

2.
Sci Rep ; 12(1): 13303, 2022 08 03.
Article in English | MEDLINE | ID: mdl-35922467

ABSTRACT

Controlled human malaria infection (CHMI) using cryopreserved non-attenuated Plasmodium falciparum sporozoites (PfSPZ) offers a unique opportunity to investigate naturally acquired immunity (NAI). By analyzing blood samples from 5 malaria-naïve European and 20 African adults with lifelong exposure to malaria, before, 5, and 11 days after direct venous inoculation (DVI) with SanariaR PfSPZ Challenge, we assessed the immunological patterns associated with control of microscopic and submicroscopic parasitemia. All (5/5) European individuals developed parasitemia as defined by thick blood smear (TBS), but 40% (8/20) of the African individuals controlled their parasitemia, and therefore remained thick blood smear-negative (TBS- Africans). In the TBS- Africans, we observed higher baseline frequencies of CD4+ T cells producing interferon-gamma (IFNγ) that significantly decreased 5 days after PfSPZ DVI. The TBS- Africans, which represent individuals with either very strong and rapid blood-stage immunity or with immunity to liver stages, were stratified into subjects with sub-microscopic parasitemia (TBS-PCR+) or those with possibly sterilizing immunity (TBS-PCR-). Higher frequencies of IFNγ+TNF+CD8+ γδ T cells at baseline, which later decreased within five days after PfSPZ DVI, were associated with those who remained TBS-PCR-. These findings suggest that naturally acquired immunity is characterized by different cell types that show varying strengths of malaria parasite control. While the high frequencies of antigen responsive IFNγ+CD4+ T cells in peripheral blood keep the blood-stage parasites to a sub-microscopic level, it is the IFNγ+TNF+CD8+ γδ T cells that are associated with either immunity to the liver-stage, or rapid elimination of blood-stage parasites.


Subject(s)
Malaria Vaccines , Malaria, Falciparum , Malaria , Adult , Animals , Gabon , Humans , Interferon-gamma , Malaria, Falciparum/parasitology , Parasitemia/parasitology , Plasmodium falciparum , Sporozoites , Volunteers
3.
Front Plant Sci ; 12: 722795, 2021.
Article in English | MEDLINE | ID: mdl-34630469

ABSTRACT

The transition toward more sustainable plant protection with reduced pesticide use is difficult, because there is no "silver bullet" available among nonchemical tools. Integrating several plant protection approaches may thus be needed for efficient pest management. Recently, increasing the genetic diversity of plantations via cultivar mixing has been proposed as a possible method to reduce pest damage. However, previous studies have not addressed either the relative efficiency of exploiting cultivar mixing and intrinsic plant herbivore resistance or the potential utility of combining these approaches to increase cropping security. Here, using a full factorial experiment with 60 woodland strawberry plots, we tested for the relative and combined effect of cultivar mixing and intrinsic plant resistance on herbivore damage and yield. The experiment comprised two levels of diversity ("high" with 10 varieties and "low" with two varieties) and three levels of resistance ("resistant" comprising only varieties intrinsically resistant against strawberry leaf beetle Galerucella tenella; "susceptible" with susceptible varieties only; and "resistance mixtures" with 50:50 mixtures of resistant and susceptible varieties). The experiment was carried out over two growing seasons. Use of resistant varieties either alone or intermixed with susceptible varieties in "resistance mixtures" reduced insect herbivory. Interestingly, resistant varieties not only reduced the mean damage in "resistance mixtures" by themselves being less damaged, but also protected intermixed susceptible varieties via associational resistance. The effect of higher genetic diversity was less evident, reducing herbivory only at the highest level of herbivore damage. In general, herbivory was lowest in plots with high diversity that included at least some resistant varieties and highest in low diversity plots consisting only of susceptible varieties. Despite this, no significant difference in yield (fruit biomass) was found, indicating that strawberry may be relatively tolerant. Our results demonstrate that combined use of high genetic diversity and resistant varieties can help reduce pest damage and provide a useful tool for sustainable food production. "Resistance mixtures" may be particularly useful for sensitive food crops where susceptible varieties are high yielding that could not be completely replaced by resistant ones.

4.
Cell ; 184(15): 3915-3935.e21, 2021 07 22.
Article in English | MEDLINE | ID: mdl-34174187

ABSTRACT

Emerging evidence indicates a fundamental role for the epigenome in immunity. Here, we mapped the epigenomic and transcriptional landscape of immunity to influenza vaccination in humans at the single-cell level. Vaccination against seasonal influenza induced persistently diminished H3K27ac in monocytes and myeloid dendritic cells (mDCs), which was associated with impaired cytokine responses to Toll-like receptor stimulation. Single-cell ATAC-seq analysis revealed an epigenomically distinct subcluster of monocytes with reduced chromatin accessibility at AP-1-targeted loci after vaccination. Similar effects were observed in response to vaccination with the AS03-adjuvanted H5N1 pandemic influenza vaccine. However, this vaccine also stimulated persistently increased chromatin accessibility at interferon response factor (IRF) loci in monocytes and mDCs. This was associated with elevated expression of antiviral genes and heightened resistance to the unrelated Zika and Dengue viruses. These results demonstrate that vaccination stimulates persistent epigenomic remodeling of the innate immune system and reveal AS03's potential as an epigenetic adjuvant.


Subject(s)
Epigenomics , Immunity/genetics , Influenza Vaccines/genetics , Influenza Vaccines/immunology , Single-Cell Analysis , Transcription, Genetic , Vaccination , Adolescent , Adult , Anti-Bacterial Agents/pharmacology , Antigens, CD34/metabolism , Antiviral Agents/pharmacology , Cellular Reprogramming , Chromatin/metabolism , Cytokines/biosynthesis , Drug Combinations , Female , Gene Expression Regulation , Histones/metabolism , Humans , Immunity, Innate/genetics , Influenza A Virus, H5N1 Subtype/drug effects , Influenza A Virus, H5N1 Subtype/immunology , Interferon Type I/metabolism , Male , Myeloid Cells/metabolism , Polysorbates/pharmacology , Squalene/pharmacology , Toll-Like Receptors/metabolism , Transcription Factor AP-1/metabolism , Transcriptome/genetics , Young Adult , alpha-Tocopherol/pharmacology
5.
Nat Immunol ; 22(5): 654-665, 2021 05.
Article in English | MEDLINE | ID: mdl-33888898

ABSTRACT

Controlled human infections provide opportunities to study the interaction between the immune system and malaria parasites, which is essential for vaccine development. Here, we compared immune signatures of malaria-naive Europeans and of Africans with lifelong malaria exposure using mass cytometry, RNA sequencing and data integration, before and 5 and 11 days after venous inoculation with Plasmodium falciparum sporozoites. We observed differences in immune cell populations, antigen-specific responses and gene expression profiles between Europeans and Africans and among Africans with differing degrees of immunity. Before inoculation, an activated/differentiated state of both innate and adaptive cells, including elevated CD161+CD4+ T cells and interferon-γ production, predicted Africans capable of controlling parasitemia. After inoculation, the rapidity of the transcriptional response and clusters of CD4+ T cells, plasmacytoid dendritic cells and innate T cells were among the features distinguishing Africans capable of controlling parasitemia from susceptible individuals. These findings can guide the development of a vaccine effective in malaria-endemic regions.


Subject(s)
Adaptive Immunity/immunology , Disease Susceptibility/immunology , Malaria, Falciparum/immunology , Plasmodium falciparum/immunology , Adaptive Immunity/genetics , Adolescent , Adult , Antibodies, Protozoan/blood , Antibodies, Protozoan/immunology , Antigens, Protozoan/immunology , Black People/genetics , Dendritic Cells/immunology , Disease Susceptibility/blood , Disease Susceptibility/parasitology , Female , Healthy Volunteers , Host-Parasite Interactions/genetics , Host-Parasite Interactions/immunology , Humans , Immunity, Innate/genetics , Immunity, Innate/immunology , Interferon-gamma/metabolism , Malaria, Falciparum/blood , Malaria, Falciparum/parasitology , Male , RNA-Seq , Systems Analysis , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , White People/genetics , Young Adult
6.
Cell Host Microbe ; 28(2): 169-179, 2020 08 12.
Article in English | MEDLINE | ID: mdl-32791110

ABSTRACT

Vaccines are the most effective means available for preventing infectious diseases. However, vaccine-induced immune responses are highly variable between individuals and between populations in different regions of the world. Understanding the basis of this variation is, thus, of fundamental importance to human health. Although the factors that are associated with intra- and inter-population variation in vaccine responses are manifold, emerging evidence points to a key role for the gut microbiome in controlling immune responses to vaccination. Much of this evidence comes from studies in mice, and causal evidence for the impact of the microbiome on human immunity is sparse. However, recent studies on vaccination in subjects treated with broad-spectrum antibiotics have provided causal evidence and mechanistic insights into how the microbiota controls immune responses in humans.


Subject(s)
Gastrointestinal Microbiome/immunology , Immunogenicity, Vaccine/immunology , Vaccination , Vaccines/immunology , Animals , Anti-Bacterial Agents/pharmacology , Gastrointestinal Microbiome/drug effects , Humans , Mice , Mucous Membrane/microbiology , Probiotics/pharmacology
7.
Midwifery ; 71: 1-11, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30623790

ABSTRACT

OBJECTIVE: Although smoking during pregnancy can have severe health consequences for the (unborn) child, 9% of Dutch pregnant women smoke at any time during their pregnancy. Midwives in the Netherlands are a responsible party in the provision of quit-smoking counselling for pregnant women by means of the 7-step `V-MIS' intervention, but in practice the implementation appears to be suboptimal. The purpose of the present study was to assess the provision of quit-smoking counselling by midwives, and to clarify the nature and extent of any existing barriers and needs in the provision of quit-smoking counselling in Dutch midwifery settings. METHODS: An online questionnaire to the target population of Dutch midwives (N ≈ 3150) was set out in the spring of 2016. The questionnaire included items on the provision of quit-smoking counselling for pregnant women, and on possible barriers and needs regarding the provision of this counselling. Descriptive statistics were used to analyse weighed data from 135 midwives representative for the Dutch setting in terms of age, function, and region. RESULTS: Eighty-one percent of the midwives inquire about smoking profile (V-MIS step 1) but only 10% go through all the V-MIS counselling steps (i.e. up to discussing postnatal passive smoking and smoke free breastfeeding, step 7). Although 74% of the midwives regard it as their task to provide quit-smoking guidance to pregnant women, 77% perceive referral to a professional as a useful strategy (mostly to the GP; 74%). For 61% of the midwives, their clients' lack of motivation undermines the provision of quit-smoking counselling. Other hindering factors are the perceived lack of free brochures (54%), simple tools or gadgets (51%), and financial consequences for the midwife (37%) and/or the client (22%). CONCLUSION: The smoking cessation intervention strategy currently imposed in Dutch midwifery practices (V-MIS) is being used by midwives, however its implementation may considerably benefit from strengthening skills in motivational interviewing techniques, provision of supporting materials, and structural embedding of GP referral. Based on the study's findings, practical recommendations are made to facilitate the provision of quit-smoking counselling in (international) midwifery settings.


Subject(s)
Counseling/standards , Guideline Adherence/standards , Midwifery/methods , Smoking Cessation/statistics & numerical data , Adult , Counseling/statistics & numerical data , Female , Guidelines as Topic , Humans , Middle Aged , Midwifery/standards , Midwifery/statistics & numerical data , Netherlands/epidemiology , Pregnancy , Pregnancy Complications/epidemiology , Smoking/epidemiology , Surveys and Questionnaires
8.
Sci Rep ; 7(1): 18039, 2017 12 21.
Article in English | MEDLINE | ID: mdl-29269840

ABSTRACT

Heart failure after myocardial infarction (MI) depends on infarct size and adverse left ventricular (LV) remodelling, both influenced by the inflammatory response. Leukocyte-associated immunoglobulin-like receptor 1 (LAIR-1) is an inhibitory receptor of ITAM-dependent cell activation, present on almost all immune cells. We investigated regulation of LAIR-1 leukocyte expression after MI in patients and hypothesized that its absence in a mouse model of MI would increase infarct size and adverse remodelling. In patients, LAIR-1 expression was increased 3 days compared to 6 weeks after MI on circulating monocytes (24.8 ± 5.3 vs. 21.2 ± 5.1 MFI, p = 0.008) and neutrophils (12.9 ± 4.7 vs. 10.6 ± 3.1 MFI, p = 0.046). In WT and LAIR-1-/- mice, infarct size after ischemia-reperfusion injury was comparable (37.0 ± 14.5 in WT vs. 39.4 ± 12.2% of the area at risk in LAIR-1-/-, p = 0.63). Remodelling after permanent left coronary artery ligation did not differ between WT and LAIR-1-/- mice (end-diastolic volume 133.3 ± 19.3 vs. 132.1 ± 27.9 µL, p = 0.91 and end-systolic volume 112.1 ± 22.2 vs. 106.9 ± 33.5 µL, p = 0.68). Similarly, no differences were observed in inflammatory cell influx or fibrosis. In conclusion, LAIR-1 expression on monocytes and neutrophils is increased in the acute phase after MI in patients, but the absence of LAIR-1 in mice does not influence infarct size, inflammation, fibrosis or adverse cardiac remodelling.


Subject(s)
Myocardial Infarction/metabolism , Myocardium/metabolism , Receptors, Immunologic/metabolism , Reperfusion Injury/metabolism , Aged , Animals , Disease Models, Animal , Female , Fibrosis/genetics , Fibrosis/metabolism , Fibrosis/pathology , Gene Expression Regulation , Humans , Inflammation/genetics , Inflammation/metabolism , Inflammation/pathology , Male , Mice , Mice, Knockout , Middle Aged , Monocytes/metabolism , Myocardial Infarction/genetics , Myocardial Infarction/pathology , Myocardium/pathology , Neutrophils/metabolism , Receptors, Immunologic/genetics , Reperfusion Injury/genetics , Reperfusion Injury/pathology , Ventricular Remodeling/physiology
9.
Sci Rep ; 7(1): 8844, 2017 08 18.
Article in English | MEDLINE | ID: mdl-28821806

ABSTRACT

Both γδ T cells and CD4+ T cells have been implicated in immunity to malaria, but their association with natural gain or loss of infection has not been studied before. Therefore, we followed up asymptomatic children living in an area endemic for malaria in Indonesia for 21 months. The percentage of γδ T cells was related to both current and previous infection, with higher percentages in infected than uninfected children and declining after infections resolve. Infected children also had higher levels of Th1 and Th17 cells, lower levels of CD25Hi FOXP3+ regulatory T cells (Tregs), but similar levels of Th2 cells as compared to uninfected children. However, TNF, IFN-γ, and IL-17 cytokine responses to Plasmodium falciparum-infected red blood cells (PfRBCs) were similar, while IL-5 and IL-13 responses were lower in infected children. Furthermore, infected children had more phenotypically exhausted PD-1+ CD4+ T cells, more Tregs expressing TNF-RII, and higher IL-10 responses to PfRBCs, which persisted following resolution of infection. Altogether, this study demonstrates that asymptomatic malaria infection is associated with some long-lasting changes in the frequencies and immunoregulation of circulating innate and adaptive T cells, which might in part explain how pre-exposure to malaria affects responses to subsequent immunological challenges.


Subject(s)
Asymptomatic Infections/epidemiology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Malaria/epidemiology , Malaria/immunology , Receptors, Antigen, T-Cell, gamma-delta/metabolism , Adolescent , Age Factors , Child , Child, Preschool , Female , Humans , Indonesia/epidemiology , Longitudinal Studies , Lymphocyte Activation/immunology , Lymphocyte Count , Malaria/parasitology , Male , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
10.
J Magn Reson Imaging ; 45(1): 132-138, 2017 01.
Article in English | MEDLINE | ID: mdl-27309545

ABSTRACT

PURPOSE: Recently, it was shown that a significantly higher T1ρ is found in compact myocardial fibrosis after chronic myocardial infarction. In this study, we investigated the feasibility of native T1ρ -mapping for the detection of diffuse myocardial fibrosis in patients with dilated cardiomyopathy (DCM). MATERIALS AND METHODS: T1ρ -mapping was performed on three explanted hearts from DCM patients at 3 Tesla (T). Histological fibrosis quantification was performed, and compared with the T1ρ -relaxation times in the heart. Furthermore, twenty DCM patients underwent an MRI at 1.5T. Native T1ρ -maps, native T1 -maps, and extracellular volume (ECV)-maps were acquired. Additionally, eight healthy volunteers were scanned for reference values. RESULTS: A significant correlation (Pearson r = 0.49; P = 0.005) was found between ex vivo T1ρ -values and fibrosis fraction from histology. Additionally, a significantly higher T1ρ -relaxation time (55.2 ± 2.7 ms) was found in DCM patients compared with healthy control subjects (51.5 ± 1.2 ms) (P = 0.0024). The relation between in vivo T1ρ -values and ECV-values was significant (Pearson r = 0.66). No significant relation was found between native T1 - and ECV-values in this study (P = 0.89). CONCLUSION: This study showed proof of principle for the endogenous detection of diffuse myocardial fibrosis with T1ρ -MRI. Ex vivo and in vivo experiments showed promising results that T1ρ -MRI can be used to measure the extent of diffuse myocardial fibrosis in the myocardium. LEVEL OF EVIDENCE: 2 J. Magn. Reson. Imaging 2017;45:132-138.


Subject(s)
Cardiac Imaging Techniques/methods , Cardiomyopathy, Dilated/diagnostic imaging , Cardiomyopathy, Dilated/pathology , Diffusion Magnetic Resonance Imaging/methods , Endomyocardial Fibrosis/diagnostic imaging , Endomyocardial Fibrosis/pathology , Image Interpretation, Computer-Assisted/methods , Algorithms , Cardiomyopathy, Dilated/complications , Endomyocardial Fibrosis/etiology , Female , Heart Transplantation , Humans , Image Enhancement/methods , In Vitro Techniques , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Signal Processing, Computer-Assisted
11.
Proc Natl Acad Sci U S A ; 113(44): 12526-12531, 2016 11 01.
Article in English | MEDLINE | ID: mdl-27791067

ABSTRACT

In cross-sectional studies, chronic helminth infections have been associated with immunological hyporesponsiveness that can affect responses to unrelated antigens. To study the immunological effects of deworming, we conducted a cluster-randomized, double-blind, placebo-controlled trial in Indonesia and assigned 954 households to receive albendazole or placebo once every 3 mo for 2 y. Helminth-specific and nonspecific whole-blood cytokine responses were assessed in 1,059 subjects of all ages, whereas phenotyping of regulatory molecules was undertaken in 121 school-aged children. All measurements were performed before and at 9 and 21 mo after initiation of treatment. Anthelmintic treatment resulted in significant increases in proinflammatory cytokine responses to Plasmodium falciparum-infected red blood cells (PfRBCs) and mitogen, with the largest effect on TNF responses to PfRBCs at 9 mo-estimate [95% confidence interval], 0.37 [0.21-0.53], P value over time (Ptime) < 0.0001. Although the frequency of regulatory T cells did not change after treatment, there was a significant decline in the expression of the inhibitory molecule cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) on CD4+ T cells of albendazole-treated individuals, -0.060 [-0.107 to -0.013] and -0.057 [-0.105 to -0.008] at 9 and 21 mo, respectively; Ptime = 0.017. This trial shows the capacity of helminths to up-regulate inhibitory molecules and to suppress proinflammatory immune responses in humans. This could help to explain the inferior immunological responses to vaccines and lower prevalence of inflammatory diseases in low- compared with high-income countries.


Subject(s)
Albendazole/therapeutic use , Community-Acquired Infections/prevention & control , Helminthiasis/drug therapy , Helminths/drug effects , Adolescent , Adult , Animals , Anthelmintics/therapeutic use , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CTLA-4 Antigen/immunology , CTLA-4 Antigen/metabolism , Child , Community-Acquired Infections/immunology , Community-Acquired Infections/parasitology , Cross-Sectional Studies , Cytokines/blood , Cytokines/immunology , Double-Blind Method , Female , Helminthiasis/epidemiology , Helminthiasis/immunology , Helminths/immunology , Host-Parasite Interactions/drug effects , Host-Parasite Interactions/immunology , Humans , Indonesia/epidemiology , Male , Plasmodium falciparum/drug effects , Plasmodium falciparum/immunology , Prevalence , Treatment Outcome , Young Adult
12.
Sci Rep ; 6: 28207, 2016 06 16.
Article in English | MEDLINE | ID: mdl-27306703

ABSTRACT

Immunoglobulin G (IgG) Fc N-glycosylation affects antibody-mediated effector functions and varies with inflammation rooted in both communicable and non-communicable diseases. Worldwide, communicable and non-communicable diseases tend to segregate geographically. Therefore, we studied whether IgG Fc N-glycosylation varies in populations with different environmental exposures in different parts of the world. IgG Fc N-glycosylation was analysed in serum/plasma of 700 school-age children from different communities of Gabon, Ghana, Ecuador, the Netherlands and Germany. IgG1 galactosylation levels were generally higher in more affluent countries and in more urban communities. High IgG1 galactosylation levels correlated with low total IgE levels, low C-reactive protein levels and low prevalence of parasitic infections. Linear mixed modelling showed that only positivity for parasitic infections was a significant predictor of reduced IgG1 galactosylation levels. That IgG1 galactosylation is a predictor of immune activation is supported by the observation that asthmatic children seemed to have reduced IgG1 galactosylation levels as well. This indicates that IgG1 galactosylation levels could be used as a biomarker for immune activation of populations, providing a valuable tool for studies examining the epidemiological transition from communicable to non-communicable diseases.


Subject(s)
Communicable Diseases/immunology , Immunoglobulin G/chemistry , Polysaccharides/chemistry , Receptors, Fc/chemistry , Schistosoma/immunology , Schistosomiasis/immunology , Adolescent , Animals , Biomarkers/chemistry , C-Reactive Protein/metabolism , Child , Child, Preschool , Ecuador , Female , Gabon , Germany , Ghana , Glycosylation , Humans , Immunoglobulin E/blood , Immunoglobulin G/blood , Immunoglobulin G/immunology , Inflammation/immunology , Male , Netherlands , Schistosomiasis/parasitology
13.
Cardiorenal Med ; 5(3): 208-18, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26195973

ABSTRACT

BACKGROUND: Renal failure is associated with adverse cardiac remodeling and sudden cardiac death. The mechanism leading to enhanced arrhythmogenicity in the cardiorenal syndrome is unclear. The aim of this study was to characterize electrophysiological and tissue alterations correlated with enhanced arrhythmogenicity in two distinct mouse models of renal failure. METHODS: Thirty-week-old 129Sv mice received a high-salt diet and deoxycorticosterone acetate (DOCA) for 8 weeks, followed by an additional period of high-salt diet for 27 weeks (DOCA-salt aged model). Adult CD-1 mice were submitted to 5/6-subtotal nephrectomy (SNx) and treated for 11 weeks with a high-salt diet (SNx-salt adult model). Vulnerability to arrhythmia as well as conduction velocities (CVs) of the hearts were determined ex vivo with epicardial mapping. Subsequently, the hearts were characterized for connexin 43 (Cx43) and fibrosis. RESULTS: DOCA-salt and SNx-salt mice developed renal dysfunction characterized by albuminuria. Heart, lung and kidney weights were increased in DOCA-salt mice. Both DOCA-salt and SNx-salt mice were highly susceptible to ventricular arrhythmias. DOCA-salt mice had a significant decrease in both longitudinal and transversal CV in the left ventricle. Histological analysis revealed a significant reduction in Cx43 expression as well as an increase in interstitial fibrosis in both DOCA-salt and SNx-salt mice. CONCLUSION: DOCA-salt and SNx-salt treatment induced renal dysfunction, which resulted in structural and electrical cardiac remodeling and enhanced arrhythmogenicity. The reduced Cx43 expression and increased fibrosis levels in these hearts are likely candidates for the formation of the arrhythmogenic substrate.

14.
PLoS One ; 9(12): e114630, 2014.
Article in English | MEDLINE | ID: mdl-25531674

ABSTRACT

BACKGROUND: Children who have been exposed in utero to maternal filarial infection are immunologically less responsive to filarial antigens, have less pathology, and are more susceptible to acquire infection than offspring of uninfected mothers. Moreover children from filaria infected mothers have been shown to be less responsive to vaccination as a consequence of an impairment of their immune response. However, it is not well known how in utero exposure to parasite antigens affects cellular immune responses. METHODOLOGY: Here, 30 pregnant women were examined for the presence of microfilaria of Loa loa and Mansonella perstans in peripheral blood. At delivery, cord blood mononuclear cells (CBMC) were obtained and the CD4+T cells were phenotyped by expression of the transcription factors Tbet, RORγt, and FOXP3. RESULTS: No significant difference was observed between newborns from infected versus uninfected mothers in the frequencies of total CD4+T cells and CD4+T cells subsets including CD4+Tbet+, CD4+RORγt+ T and CD4+CD25hiFOXP3+ T cells. However, there was a negative association between CD4+CD25hiFOXP3+T cells and CD4+Tbet+ as well as CD4+RORγt+ T cells in the infected group only (B = -0.242, P = 0.002; B = -0.178, P = 0.013 respectively). CONCLUSION: Our results suggest that filarial infection during pregnancy leads to an expansion of functionally active regulatory T cells that keep TH1 and TH17 in check.


Subject(s)
CD4-Positive T-Lymphocytes/metabolism , Fetal Blood/cytology , Forkhead Transcription Factors/metabolism , Interleukin-2 Receptor alpha Subunit/metabolism , Microfilariae/isolation & purification , Nuclear Receptor Subfamily 1, Group F, Member 3/metabolism , T-Box Domain Proteins/metabolism , Adult , Animals , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/immunology , Female , Humans , Infant, Newborn , Loa/growth & development , Loa/physiology , Mansonella/growth & development , Mansonella/physiology , Mothers , Pregnancy , T-Lymphocytes, Regulatory/cytology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Th1 Cells/cytology , Th1 Cells/immunology , Th1 Cells/metabolism , Th17 Cells/cytology , Th17 Cells/immunology , Th17 Cells/metabolism
15.
Mol Imaging ; 132014.
Article in English | MEDLINE | ID: mdl-25249247

ABSTRACT

Cardiac fibrosis is a major hallmark of cardiac diseases. For evaluation of cardiac fibrosis, the development of highly specific and preferably noninvasive methods is desired. Our aim was to evaluate CNA35, a protein known to specifically bind to collagen, as a specific marker of cardiac fibrosis. Fluorescently labeled CNA35 was applied ex vivo on tissue sections of fibrotic rat, mouse, and canine myocardium. After quantification of CNA35, sections were examined with picrosirius red (PSR) and compared to CNA35. Furthermore, fluorescently labeled CNA35 was administered in vivo in mice. Hearts were isolated, and CNA35 labeling was examined in tissue sections. Serial sections were histologically examined with PSR. Ex vivo application of CNA35 showed specific binding to collagen and a high correlation with PSR (Pearson r  =  .86 for mice/rats and r  =  .98 for canine; both p < .001). After in vivo administration, CNA35 labeling was observed around individual cardiomyocytes, indicating its ability to penetrate cardiac endothelium. High correlation was observed between CNA35 and PSR (r  =  .91, p < .001). CNA35 specifically binds to cardiac collagen and can cross the endothelial barrier. Therefore, labeled CNA35 is useful to specifically detect collagen both ex vivo and in vivo and potentially can be converted to a noninvasive method to detect cardiac fibrosis.


Subject(s)
Cell Adhesion Molecules/analysis , Cell Adhesion Molecules/metabolism , Myocytes, Cardiac/metabolism , Animals , Biomarkers/analysis , Biomarkers/chemistry , Cell Adhesion Molecules/chemistry , Dogs , Endomyocardial Fibrosis/diagnosis , Endomyocardial Fibrosis/pathology , Fluorescein-5-isothiocyanate , Mice , Rats
16.
Immunology ; 143(4): 569-77, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24924958

ABSTRACT

Differences in lifestyle and break with natural environment appear to be associated with changes in the immune system resulting in various adverse health effects. Although genetics can have a major impact on the immune system and disease susceptibility, the contribution of environmental factors is thought to be substantial. Here, we investigated the immunological profile of healthy volunteers living in a rural and an urban area of a developing African country (Senegal), and in a European country (the Netherlands). Using flow cytometry, we investigated T helper type 1 (Th1), Th2, Th17, Th22 and regulatory T cells, as well as CD4(+) T-cell and B-cell activation markers, and subsets of memory T and B cells in the peripheral blood. Rural Senegalese had significantly higher frequencies of Th1, Th2 and Th22 cells, memory CD4(+) T and B cells, as well as activated CD4(+) T and B cells compared with urban Senegalese and urban Dutch people. Within the Senegalese population, rural paritcipants displayed significantly higher frequencies of Th2 and Th22 cells, as well as higher pro-inflammatory and T-cell activation and memory profiles compared with the urban population. The greater magnitude of immune activation and the enlarged memory pool, together with Th2 polarization, seen in rural participants from Africa, followed by urban Africans and Europeans suggest that environmental changes may define immunological footprints, which could have consequences for disease patterns in general and vaccine responses in particular.


Subject(s)
Adaptation, Biological/immunology , Immune System/physiology , Life Style , Urbanization , Adult , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Cytokines/metabolism , Female , Humans , Immunologic Memory , Immunophenotyping , Inflammation Mediators/metabolism , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Lymphocyte Count , Male , Netherlands , Rural Population , Senegal , Urban Population , Young Adult
17.
PLoS One ; 9(4): e95241, 2014.
Article in English | MEDLINE | ID: mdl-24743542

ABSTRACT

Although differences in immunological responses between populations have been found in terms of vaccine efficacy, immune responses to infections and prevalence of chronic inflammatory diseases, the mechanisms responsible for these differences are not well understood. Therefore, innate cytokine responses mediated by various classes of pattern-recognition receptors including Toll-like receptors (TLR), C-type lectin receptors (CLRs) and nucleotide-binding oligomerisation domain-like receptors (NLRs) were compared between Dutch (European), semi-urban and rural Gabonese (African) children. Whole blood was stimulated for 24 hours and the pro-inflammatory tumor necrosis factor (TNF) and the anti-inflammatory/regulatory interleukin-10 (IL-10) cytokines in culture supernatant were measured by enzyme-linked immunosorbent assay (ELISA). Gabonese children had a lower pro-inflammatory response to poly(I:C) (TLR3 ligand), but a higher pro-inflammatory response to FSL-1 (TLR2/6 ligand), Pam3 (TLR2/1 ligand) and LPS (TLR4 ligand) compared to Dutch children. Anti-inflammatory responses to Pam3 were also higher in Gabonese children. Non-TLR ligands did not induce substantial cytokine production on their own. Interaction between various TLR and non-TLR receptors was further assessed, but no differences were found between the three populations. In conclusion, using a field applicable assay, significant differences were observed in cytokine responses between European and African children to TLR ligands, but not to non-TLR ligands.


Subject(s)
Black People , Immunity, Innate/immunology , Immunity, Innate/physiology , Interleukin-10/immunology , Interleukin-6/immunology , White People , Adolescent , Child , Female , Gabon , Humans , Male , Netherlands , Toll-Like Receptors/agonists , Toll-Like Receptors/immunology
18.
J Med Internet Res ; 16(3): e82, 2014 Mar 21.
Article in English | MEDLINE | ID: mdl-24657434

ABSTRACT

BACKGROUND: Preventing smoking initiation among adolescents is crucial to reducing tobacco-caused death and disease. This study focuses on the effectiveness of a Web-based computer-tailored smoking prevention intervention aimed at adolescents. OBJECTIVE: The intent of the study was to describe the intervention characteristics and to show the effectiveness and results of a randomized controlled trial. We hypothesized that the intervention would prevent smoking initiation among Dutch secondary school students aged 10-20 years and would have the largest smoking prevention effect among the age cohort of 14-16 years, as smoking uptake in that period is highest. METHODS: The intervention consisted of a questionnaire and fully automated computer-tailored feedback on intention to start smoking and motivational determinants. A total of 89 secondary schools were recruited via postal mail and randomized into either the computer-tailored intervention condition or the control condition. Participants had to complete a Web-based questionnaire at baseline and at 6-month follow-up. Data on smoking initiation were collected from 897 students from these schools. To identify intervention effects, multilevel logistic regression analyses were conducted using multiple imputation. RESULTS: Smoking initiation among students aged 10-20 years was borderline significantly lower in the experimental condition as compared to the control condition 6 months after baseline (OR 0.25, 95% CI 0.05-1.21, P=.09). Additional analyses of the data for the 14-16 year age group showed a significant effect, with 11.5% (24/209) of the students in the control condition reporting initiation compared to 5.7% (10/176) in the experimental condition (OR 0.22, 95% CI 0.05-1.02, P=.05). No moderation effects were found regarding gender and educational level. CONCLUSIONS: The findings of this study suggest that computer-tailored smoking prevention programs are a promising way of preventing smoking initiation among adolescents for at least 6 months, in particular among the age cohort of 14-16 years. Further research is needed to focus on long-term effects. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN): 77864351; http://www.controlled-trials.com/ISRCTN77864351 (Archived by WebCite at http://www.webcitation.org/6BSLKSTm5).


Subject(s)
Health Promotion/methods , Internet , Smoking Prevention , Adolescent , Child , Electronic Mail , Feedback , Female , Humans , Male , Netherlands , Surveys and Questionnaires , Young Adult
19.
J Infect Dis ; 207(1): 186-95, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23087431

ABSTRACT

BACKGROUND: Schistosome infections are often clinically silent, but some individuals develop severe pathological reactions. In several disease processes, T-helper 17 (Th17) cells have been linked to tissue injuries, while regulatory T cells (Tregs) are thought to downmodulate inflammatory reactions. We assessed whether bladder pathology in human Schistosoma haematobium infection is related to the balance of Th17 cells and Tregs. We used a murine model of Schistosoma mansoni infection to further investigate whether the peripheral profiles reflected ongoing events in tissues. METHODS: We characterized T-helper cell subsets in the peripheral blood of children residing in a S. haematobium-endemic area and in the peripheral blood, spleen, and hepatic granulomas of S. mansoni-infected high-pathology CBA mice and low-pathology C57BL/6 mice. RESULTS: S. haematobium-infected children with bladder pathology had a significantly higher percentage of Th17 cells than those without pathology. Moreover, the Th17/Treg ratios were significantly higher in infected children with pathology, compared with infected children without pathology. Percentages of interleukin 17-producing cells were significantly higher in spleen and granulomas of CBA mice, compared with C57BL/6 mice. This difference was also reflected in the peripheral blood. CONCLUSIONS: This is the first study to indicate that Th17 cells may be involved in the pathogenesis of human schistosomiasis.


Subject(s)
Schistosoma haematobium/immunology , Schistosomiasis haematobia/pathology , T-Lymphocytes, Regulatory/immunology , Th17 Cells/immunology , Adolescent , Adult , Animals , Child , Child, Preschool , Cytokines/immunology , Female , Granulocytes/pathology , Host-Parasite Interactions/immunology , Humans , Interleukin-17/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Inbred CBA , Middle Aged , Schistosoma mansoni/immunology , Schistosomiasis haematobia/parasitology , Schistosomiasis mansoni/parasitology , Schistosomiasis mansoni/pathology , Spleen/parasitology , Spleen/pathology , Urinary Bladder/parasitology , Urinary Bladder/pathology , Young Adult
20.
Phys Rev Lett ; 108(26): 267403, 2012 Jun 29.
Article in English | MEDLINE | ID: mdl-23005013

ABSTRACT

We present the first single-shot images of ferromagnetic, nanoscale spin order taken with femtosecond x-ray pulses. X-ray-induced electron and spin dynamics can be outrun with pulses shorter than 80 fs in the investigated fluence regime, and no permanent aftereffects in the samples are observed below a fluence of 25 mJ/cm(2). Employing resonant spatially muliplexed x-ray holography results in a low imaging threshold of 5 mJ/cm(2). Our results open new ways to combine ultrafast laser spectroscopy with sequential snapshot imaging on a single sample, generating a movie of excited state dynamics.

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